xref: /linux/net/ipv4/ip_sockglue.c (revision 1795cf48b322b4d19230a40dbe7181acedd34a94)
1 /*
2  * INET		An implementation of the TCP/IP protocol suite for the LINUX
3  *		operating system.  INET is implemented using the  BSD Socket
4  *		interface as the means of communication with the user level.
5  *
6  *		The IP to API glue.
7  *
8  * Authors:	see ip.c
9  *
10  * Fixes:
11  *		Many		:	Split from ip.c , see ip.c for history.
12  *		Martin Mares	:	TOS setting fixed.
13  *		Alan Cox	:	Fixed a couple of oopses in Martin's
14  *					TOS tweaks.
15  *		Mike McLagan	:	Routing by source
16  */
17 
18 #include <linux/module.h>
19 #include <linux/types.h>
20 #include <linux/mm.h>
21 #include <linux/skbuff.h>
22 #include <linux/ip.h>
23 #include <linux/icmp.h>
24 #include <linux/inetdevice.h>
25 #include <linux/netdevice.h>
26 #include <net/sock.h>
27 #include <net/ip.h>
28 #include <net/icmp.h>
29 #include <net/tcp_states.h>
30 #include <linux/udp.h>
31 #include <linux/igmp.h>
32 #include <linux/netfilter.h>
33 #include <linux/route.h>
34 #include <linux/mroute.h>
35 #include <net/route.h>
36 #include <net/xfrm.h>
37 #include <net/compat.h>
38 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
39 #include <net/transp_v6.h>
40 #endif
41 
42 #include <linux/errqueue.h>
43 #include <asm/uaccess.h>
44 
45 #define IP_CMSG_PKTINFO		1
46 #define IP_CMSG_TTL		2
47 #define IP_CMSG_TOS		4
48 #define IP_CMSG_RECVOPTS	8
49 #define IP_CMSG_RETOPTS		16
50 #define IP_CMSG_PASSSEC		32
51 
52 /*
53  *	SOL_IP control messages.
54  */
55 
56 static void ip_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb)
57 {
58 	struct in_pktinfo info;
59 	struct rtable *rt = skb->rtable;
60 
61 	info.ipi_addr.s_addr = ip_hdr(skb)->daddr;
62 	if (rt) {
63 		info.ipi_ifindex = rt->rt_iif;
64 		info.ipi_spec_dst.s_addr = rt->rt_spec_dst;
65 	} else {
66 		info.ipi_ifindex = 0;
67 		info.ipi_spec_dst.s_addr = 0;
68 	}
69 
70 	put_cmsg(msg, SOL_IP, IP_PKTINFO, sizeof(info), &info);
71 }
72 
73 static void ip_cmsg_recv_ttl(struct msghdr *msg, struct sk_buff *skb)
74 {
75 	int ttl = ip_hdr(skb)->ttl;
76 	put_cmsg(msg, SOL_IP, IP_TTL, sizeof(int), &ttl);
77 }
78 
79 static void ip_cmsg_recv_tos(struct msghdr *msg, struct sk_buff *skb)
80 {
81 	put_cmsg(msg, SOL_IP, IP_TOS, 1, &ip_hdr(skb)->tos);
82 }
83 
84 static void ip_cmsg_recv_opts(struct msghdr *msg, struct sk_buff *skb)
85 {
86 	if (IPCB(skb)->opt.optlen == 0)
87 		return;
88 
89 	put_cmsg(msg, SOL_IP, IP_RECVOPTS, IPCB(skb)->opt.optlen,
90 		 ip_hdr(skb) + 1);
91 }
92 
93 
94 static void ip_cmsg_recv_retopts(struct msghdr *msg, struct sk_buff *skb)
95 {
96 	unsigned char optbuf[sizeof(struct ip_options) + 40];
97 	struct ip_options * opt = (struct ip_options*)optbuf;
98 
99 	if (IPCB(skb)->opt.optlen == 0)
100 		return;
101 
102 	if (ip_options_echo(opt, skb)) {
103 		msg->msg_flags |= MSG_CTRUNC;
104 		return;
105 	}
106 	ip_options_undo(opt);
107 
108 	put_cmsg(msg, SOL_IP, IP_RETOPTS, opt->optlen, opt->__data);
109 }
110 
111 static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
112 {
113 	char *secdata;
114 	u32 seclen, secid;
115 	int err;
116 
117 	err = security_socket_getpeersec_dgram(NULL, skb, &secid);
118 	if (err)
119 		return;
120 
121 	err = security_secid_to_secctx(secid, &secdata, &seclen);
122 	if (err)
123 		return;
124 
125 	put_cmsg(msg, SOL_IP, SCM_SECURITY, seclen, secdata);
126 	security_release_secctx(secdata, seclen);
127 }
128 
129 
130 void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb)
131 {
132 	struct inet_sock *inet = inet_sk(skb->sk);
133 	unsigned flags = inet->cmsg_flags;
134 
135 	/* Ordered by supposed usage frequency */
136 	if (flags & 1)
137 		ip_cmsg_recv_pktinfo(msg, skb);
138 	if ((flags>>=1) == 0)
139 		return;
140 
141 	if (flags & 1)
142 		ip_cmsg_recv_ttl(msg, skb);
143 	if ((flags>>=1) == 0)
144 		return;
145 
146 	if (flags & 1)
147 		ip_cmsg_recv_tos(msg, skb);
148 	if ((flags>>=1) == 0)
149 		return;
150 
151 	if (flags & 1)
152 		ip_cmsg_recv_opts(msg, skb);
153 	if ((flags>>=1) == 0)
154 		return;
155 
156 	if (flags & 1)
157 		ip_cmsg_recv_retopts(msg, skb);
158 	if ((flags>>=1) == 0)
159 		return;
160 
161 	if (flags & 1)
162 		ip_cmsg_recv_security(msg, skb);
163 }
164 
165 int ip_cmsg_send(struct net *net, struct msghdr *msg, struct ipcm_cookie *ipc)
166 {
167 	int err;
168 	struct cmsghdr *cmsg;
169 
170 	for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
171 		if (!CMSG_OK(msg, cmsg))
172 			return -EINVAL;
173 		if (cmsg->cmsg_level != SOL_IP)
174 			continue;
175 		switch (cmsg->cmsg_type) {
176 		case IP_RETOPTS:
177 			err = cmsg->cmsg_len - CMSG_ALIGN(sizeof(struct cmsghdr));
178 			err = ip_options_get(net, &ipc->opt, CMSG_DATA(cmsg), err < 40 ? err : 40);
179 			if (err)
180 				return err;
181 			break;
182 		case IP_PKTINFO:
183 		{
184 			struct in_pktinfo *info;
185 			if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct in_pktinfo)))
186 				return -EINVAL;
187 			info = (struct in_pktinfo *)CMSG_DATA(cmsg);
188 			ipc->oif = info->ipi_ifindex;
189 			ipc->addr = info->ipi_spec_dst.s_addr;
190 			break;
191 		}
192 		default:
193 			return -EINVAL;
194 		}
195 	}
196 	return 0;
197 }
198 
199 
200 /* Special input handler for packets caught by router alert option.
201    They are selected only by protocol field, and then processed likely
202    local ones; but only if someone wants them! Otherwise, router
203    not running rsvpd will kill RSVP.
204 
205    It is user level problem, what it will make with them.
206    I have no idea, how it will masquearde or NAT them (it is joke, joke :-)),
207    but receiver should be enough clever f.e. to forward mtrace requests,
208    sent to multicast group to reach destination designated router.
209  */
210 struct ip_ra_chain *ip_ra_chain;
211 DEFINE_RWLOCK(ip_ra_lock);
212 
213 int ip_ra_control(struct sock *sk, unsigned char on, void (*destructor)(struct sock *))
214 {
215 	struct ip_ra_chain *ra, *new_ra, **rap;
216 
217 	if (sk->sk_type != SOCK_RAW || inet_sk(sk)->num == IPPROTO_RAW)
218 		return -EINVAL;
219 
220 	new_ra = on ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL;
221 
222 	write_lock_bh(&ip_ra_lock);
223 	for (rap = &ip_ra_chain; (ra=*rap) != NULL; rap = &ra->next) {
224 		if (ra->sk == sk) {
225 			if (on) {
226 				write_unlock_bh(&ip_ra_lock);
227 				kfree(new_ra);
228 				return -EADDRINUSE;
229 			}
230 			*rap = ra->next;
231 			write_unlock_bh(&ip_ra_lock);
232 
233 			if (ra->destructor)
234 				ra->destructor(sk);
235 			sock_put(sk);
236 			kfree(ra);
237 			return 0;
238 		}
239 	}
240 	if (new_ra == NULL) {
241 		write_unlock_bh(&ip_ra_lock);
242 		return -ENOBUFS;
243 	}
244 	new_ra->sk = sk;
245 	new_ra->destructor = destructor;
246 
247 	new_ra->next = ra;
248 	*rap = new_ra;
249 	sock_hold(sk);
250 	write_unlock_bh(&ip_ra_lock);
251 
252 	return 0;
253 }
254 
255 void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
256 		   __be16 port, u32 info, u8 *payload)
257 {
258 	struct inet_sock *inet = inet_sk(sk);
259 	struct sock_exterr_skb *serr;
260 
261 	if (!inet->recverr)
262 		return;
263 
264 	skb = skb_clone(skb, GFP_ATOMIC);
265 	if (!skb)
266 		return;
267 
268 	serr = SKB_EXT_ERR(skb);
269 	serr->ee.ee_errno = err;
270 	serr->ee.ee_origin = SO_EE_ORIGIN_ICMP;
271 	serr->ee.ee_type = icmp_hdr(skb)->type;
272 	serr->ee.ee_code = icmp_hdr(skb)->code;
273 	serr->ee.ee_pad = 0;
274 	serr->ee.ee_info = info;
275 	serr->ee.ee_data = 0;
276 	serr->addr_offset = (u8 *)&(((struct iphdr *)(icmp_hdr(skb) + 1))->daddr) -
277 				   skb_network_header(skb);
278 	serr->port = port;
279 
280 	if (skb_pull(skb, payload - skb->data) != NULL) {
281 		skb_reset_transport_header(skb);
282 		if (sock_queue_err_skb(sk, skb) == 0)
283 			return;
284 	}
285 	kfree_skb(skb);
286 }
287 
288 void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 port, u32 info)
289 {
290 	struct inet_sock *inet = inet_sk(sk);
291 	struct sock_exterr_skb *serr;
292 	struct iphdr *iph;
293 	struct sk_buff *skb;
294 
295 	if (!inet->recverr)
296 		return;
297 
298 	skb = alloc_skb(sizeof(struct iphdr), GFP_ATOMIC);
299 	if (!skb)
300 		return;
301 
302 	skb_put(skb, sizeof(struct iphdr));
303 	skb_reset_network_header(skb);
304 	iph = ip_hdr(skb);
305 	iph->daddr = daddr;
306 
307 	serr = SKB_EXT_ERR(skb);
308 	serr->ee.ee_errno = err;
309 	serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
310 	serr->ee.ee_type = 0;
311 	serr->ee.ee_code = 0;
312 	serr->ee.ee_pad = 0;
313 	serr->ee.ee_info = info;
314 	serr->ee.ee_data = 0;
315 	serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
316 	serr->port = port;
317 
318 	__skb_pull(skb, skb_tail_pointer(skb) - skb->data);
319 	skb_reset_transport_header(skb);
320 
321 	if (sock_queue_err_skb(sk, skb))
322 		kfree_skb(skb);
323 }
324 
325 /*
326  *	Handle MSG_ERRQUEUE
327  */
328 int ip_recv_error(struct sock *sk, struct msghdr *msg, int len)
329 {
330 	struct sock_exterr_skb *serr;
331 	struct sk_buff *skb, *skb2;
332 	struct sockaddr_in *sin;
333 	struct {
334 		struct sock_extended_err ee;
335 		struct sockaddr_in	 offender;
336 	} errhdr;
337 	int err;
338 	int copied;
339 
340 	err = -EAGAIN;
341 	skb = skb_dequeue(&sk->sk_error_queue);
342 	if (skb == NULL)
343 		goto out;
344 
345 	copied = skb->len;
346 	if (copied > len) {
347 		msg->msg_flags |= MSG_TRUNC;
348 		copied = len;
349 	}
350 	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
351 	if (err)
352 		goto out_free_skb;
353 
354 	sock_recv_timestamp(msg, sk, skb);
355 
356 	serr = SKB_EXT_ERR(skb);
357 
358 	sin = (struct sockaddr_in *)msg->msg_name;
359 	if (sin) {
360 		sin->sin_family = AF_INET;
361 		sin->sin_addr.s_addr = *(__be32 *)(skb_network_header(skb) +
362 						   serr->addr_offset);
363 		sin->sin_port = serr->port;
364 		memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
365 	}
366 
367 	memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
368 	sin = &errhdr.offender;
369 	sin->sin_family = AF_UNSPEC;
370 	if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP) {
371 		struct inet_sock *inet = inet_sk(sk);
372 
373 		sin->sin_family = AF_INET;
374 		sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
375 		sin->sin_port = 0;
376 		memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
377 		if (inet->cmsg_flags)
378 			ip_cmsg_recv(msg, skb);
379 	}
380 
381 	put_cmsg(msg, SOL_IP, IP_RECVERR, sizeof(errhdr), &errhdr);
382 
383 	/* Now we could try to dump offended packet options */
384 
385 	msg->msg_flags |= MSG_ERRQUEUE;
386 	err = copied;
387 
388 	/* Reset and regenerate socket error */
389 	spin_lock_bh(&sk->sk_error_queue.lock);
390 	sk->sk_err = 0;
391 	if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
392 		sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
393 		spin_unlock_bh(&sk->sk_error_queue.lock);
394 		sk->sk_error_report(sk);
395 	} else
396 		spin_unlock_bh(&sk->sk_error_queue.lock);
397 
398 out_free_skb:
399 	kfree_skb(skb);
400 out:
401 	return err;
402 }
403 
404 
405 /*
406  *	Socket option code for IP. This is the end of the line after any TCP,UDP etc options on
407  *	an IP socket.
408  */
409 
410 static int do_ip_setsockopt(struct sock *sk, int level,
411 			    int optname, char __user *optval, int optlen)
412 {
413 	struct inet_sock *inet = inet_sk(sk);
414 	int val=0,err;
415 
416 	if (((1<<optname) & ((1<<IP_PKTINFO) | (1<<IP_RECVTTL) |
417 			     (1<<IP_RECVOPTS) | (1<<IP_RECVTOS) |
418 			     (1<<IP_RETOPTS) | (1<<IP_TOS) |
419 			     (1<<IP_TTL) | (1<<IP_HDRINCL) |
420 			     (1<<IP_MTU_DISCOVER) | (1<<IP_RECVERR) |
421 			     (1<<IP_ROUTER_ALERT) | (1<<IP_FREEBIND) |
422 			     (1<<IP_PASSSEC))) ||
423 	    optname == IP_MULTICAST_TTL ||
424 	    optname == IP_MULTICAST_LOOP) {
425 		if (optlen >= sizeof(int)) {
426 			if (get_user(val, (int __user *) optval))
427 				return -EFAULT;
428 		} else if (optlen >= sizeof(char)) {
429 			unsigned char ucval;
430 
431 			if (get_user(ucval, (unsigned char __user *) optval))
432 				return -EFAULT;
433 			val = (int) ucval;
434 		}
435 	}
436 
437 	/* If optlen==0, it is equivalent to val == 0 */
438 
439 	if (ip_mroute_opt(optname))
440 		return ip_mroute_setsockopt(sk,optname,optval,optlen);
441 
442 	err = 0;
443 	lock_sock(sk);
444 
445 	switch (optname) {
446 	case IP_OPTIONS:
447 	{
448 		struct ip_options * opt = NULL;
449 		if (optlen > 40 || optlen < 0)
450 			goto e_inval;
451 		err = ip_options_get_from_user(sock_net(sk), &opt,
452 					       optval, optlen);
453 		if (err)
454 			break;
455 		if (inet->is_icsk) {
456 			struct inet_connection_sock *icsk = inet_csk(sk);
457 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
458 			if (sk->sk_family == PF_INET ||
459 			    (!((1 << sk->sk_state) &
460 			       (TCPF_LISTEN | TCPF_CLOSE)) &&
461 			     inet->daddr != LOOPBACK4_IPV6)) {
462 #endif
463 				if (inet->opt)
464 					icsk->icsk_ext_hdr_len -= inet->opt->optlen;
465 				if (opt)
466 					icsk->icsk_ext_hdr_len += opt->optlen;
467 				icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
468 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
469 			}
470 #endif
471 		}
472 		opt = xchg(&inet->opt, opt);
473 		kfree(opt);
474 		break;
475 	}
476 	case IP_PKTINFO:
477 		if (val)
478 			inet->cmsg_flags |= IP_CMSG_PKTINFO;
479 		else
480 			inet->cmsg_flags &= ~IP_CMSG_PKTINFO;
481 		break;
482 	case IP_RECVTTL:
483 		if (val)
484 			inet->cmsg_flags |=  IP_CMSG_TTL;
485 		else
486 			inet->cmsg_flags &= ~IP_CMSG_TTL;
487 		break;
488 	case IP_RECVTOS:
489 		if (val)
490 			inet->cmsg_flags |=  IP_CMSG_TOS;
491 		else
492 			inet->cmsg_flags &= ~IP_CMSG_TOS;
493 		break;
494 	case IP_RECVOPTS:
495 		if (val)
496 			inet->cmsg_flags |=  IP_CMSG_RECVOPTS;
497 		else
498 			inet->cmsg_flags &= ~IP_CMSG_RECVOPTS;
499 		break;
500 	case IP_RETOPTS:
501 		if (val)
502 			inet->cmsg_flags |= IP_CMSG_RETOPTS;
503 		else
504 			inet->cmsg_flags &= ~IP_CMSG_RETOPTS;
505 		break;
506 	case IP_PASSSEC:
507 		if (val)
508 			inet->cmsg_flags |= IP_CMSG_PASSSEC;
509 		else
510 			inet->cmsg_flags &= ~IP_CMSG_PASSSEC;
511 		break;
512 	case IP_TOS:	/* This sets both TOS and Precedence */
513 		if (sk->sk_type == SOCK_STREAM) {
514 			val &= ~3;
515 			val |= inet->tos & 3;
516 		}
517 		if (inet->tos != val) {
518 			inet->tos = val;
519 			sk->sk_priority = rt_tos2priority(val);
520 			sk_dst_reset(sk);
521 		}
522 		break;
523 	case IP_TTL:
524 		if (optlen<1)
525 			goto e_inval;
526 		if (val != -1 && (val < 1 || val>255))
527 			goto e_inval;
528 		inet->uc_ttl = val;
529 		break;
530 	case IP_HDRINCL:
531 		if (sk->sk_type != SOCK_RAW) {
532 			err = -ENOPROTOOPT;
533 			break;
534 		}
535 		inet->hdrincl = val ? 1 : 0;
536 		break;
537 	case IP_MTU_DISCOVER:
538 		if (val<0 || val>3)
539 			goto e_inval;
540 		inet->pmtudisc = val;
541 		break;
542 	case IP_RECVERR:
543 		inet->recverr = !!val;
544 		if (!val)
545 			skb_queue_purge(&sk->sk_error_queue);
546 		break;
547 	case IP_MULTICAST_TTL:
548 		if (sk->sk_type == SOCK_STREAM)
549 			goto e_inval;
550 		if (optlen<1)
551 			goto e_inval;
552 		if (val==-1)
553 			val = 1;
554 		if (val < 0 || val > 255)
555 			goto e_inval;
556 		inet->mc_ttl = val;
557 		break;
558 	case IP_MULTICAST_LOOP:
559 		if (optlen<1)
560 			goto e_inval;
561 		inet->mc_loop = !!val;
562 		break;
563 	case IP_MULTICAST_IF:
564 	{
565 		struct ip_mreqn mreq;
566 		struct net_device *dev = NULL;
567 
568 		if (sk->sk_type == SOCK_STREAM)
569 			goto e_inval;
570 		/*
571 		 *	Check the arguments are allowable
572 		 */
573 
574 		err = -EFAULT;
575 		if (optlen >= sizeof(struct ip_mreqn)) {
576 			if (copy_from_user(&mreq,optval,sizeof(mreq)))
577 				break;
578 		} else {
579 			memset(&mreq, 0, sizeof(mreq));
580 			if (optlen >= sizeof(struct in_addr) &&
581 			    copy_from_user(&mreq.imr_address,optval,sizeof(struct in_addr)))
582 				break;
583 		}
584 
585 		if (!mreq.imr_ifindex) {
586 			if (mreq.imr_address.s_addr == htonl(INADDR_ANY)) {
587 				inet->mc_index = 0;
588 				inet->mc_addr  = 0;
589 				err = 0;
590 				break;
591 			}
592 			dev = ip_dev_find(sock_net(sk), mreq.imr_address.s_addr);
593 			if (dev) {
594 				mreq.imr_ifindex = dev->ifindex;
595 				dev_put(dev);
596 			}
597 		} else
598 			dev = __dev_get_by_index(sock_net(sk), mreq.imr_ifindex);
599 
600 
601 		err = -EADDRNOTAVAIL;
602 		if (!dev)
603 			break;
604 
605 		err = -EINVAL;
606 		if (sk->sk_bound_dev_if &&
607 		    mreq.imr_ifindex != sk->sk_bound_dev_if)
608 			break;
609 
610 		inet->mc_index = mreq.imr_ifindex;
611 		inet->mc_addr  = mreq.imr_address.s_addr;
612 		err = 0;
613 		break;
614 	}
615 
616 	case IP_ADD_MEMBERSHIP:
617 	case IP_DROP_MEMBERSHIP:
618 	{
619 		struct ip_mreqn mreq;
620 
621 		err = -EPROTO;
622 		if (inet_sk(sk)->is_icsk)
623 			break;
624 
625 		if (optlen < sizeof(struct ip_mreq))
626 			goto e_inval;
627 		err = -EFAULT;
628 		if (optlen >= sizeof(struct ip_mreqn)) {
629 			if (copy_from_user(&mreq,optval,sizeof(mreq)))
630 				break;
631 		} else {
632 			memset(&mreq, 0, sizeof(mreq));
633 			if (copy_from_user(&mreq,optval,sizeof(struct ip_mreq)))
634 				break;
635 		}
636 
637 		if (optname == IP_ADD_MEMBERSHIP)
638 			err = ip_mc_join_group(sk, &mreq);
639 		else
640 			err = ip_mc_leave_group(sk, &mreq);
641 		break;
642 	}
643 	case IP_MSFILTER:
644 	{
645 		extern int sysctl_igmp_max_msf;
646 		struct ip_msfilter *msf;
647 
648 		if (optlen < IP_MSFILTER_SIZE(0))
649 			goto e_inval;
650 		if (optlen > sysctl_optmem_max) {
651 			err = -ENOBUFS;
652 			break;
653 		}
654 		msf = kmalloc(optlen, GFP_KERNEL);
655 		if (!msf) {
656 			err = -ENOBUFS;
657 			break;
658 		}
659 		err = -EFAULT;
660 		if (copy_from_user(msf, optval, optlen)) {
661 			kfree(msf);
662 			break;
663 		}
664 		/* numsrc >= (1G-4) overflow in 32 bits */
665 		if (msf->imsf_numsrc >= 0x3ffffffcU ||
666 		    msf->imsf_numsrc > sysctl_igmp_max_msf) {
667 			kfree(msf);
668 			err = -ENOBUFS;
669 			break;
670 		}
671 		if (IP_MSFILTER_SIZE(msf->imsf_numsrc) > optlen) {
672 			kfree(msf);
673 			err = -EINVAL;
674 			break;
675 		}
676 		err = ip_mc_msfilter(sk, msf, 0);
677 		kfree(msf);
678 		break;
679 	}
680 	case IP_BLOCK_SOURCE:
681 	case IP_UNBLOCK_SOURCE:
682 	case IP_ADD_SOURCE_MEMBERSHIP:
683 	case IP_DROP_SOURCE_MEMBERSHIP:
684 	{
685 		struct ip_mreq_source mreqs;
686 		int omode, add;
687 
688 		if (optlen != sizeof(struct ip_mreq_source))
689 			goto e_inval;
690 		if (copy_from_user(&mreqs, optval, sizeof(mreqs))) {
691 			err = -EFAULT;
692 			break;
693 		}
694 		if (optname == IP_BLOCK_SOURCE) {
695 			omode = MCAST_EXCLUDE;
696 			add = 1;
697 		} else if (optname == IP_UNBLOCK_SOURCE) {
698 			omode = MCAST_EXCLUDE;
699 			add = 0;
700 		} else if (optname == IP_ADD_SOURCE_MEMBERSHIP) {
701 			struct ip_mreqn mreq;
702 
703 			mreq.imr_multiaddr.s_addr = mreqs.imr_multiaddr;
704 			mreq.imr_address.s_addr = mreqs.imr_interface;
705 			mreq.imr_ifindex = 0;
706 			err = ip_mc_join_group(sk, &mreq);
707 			if (err && err != -EADDRINUSE)
708 				break;
709 			omode = MCAST_INCLUDE;
710 			add = 1;
711 		} else /* IP_DROP_SOURCE_MEMBERSHIP */ {
712 			omode = MCAST_INCLUDE;
713 			add = 0;
714 		}
715 		err = ip_mc_source(add, omode, sk, &mreqs, 0);
716 		break;
717 	}
718 	case MCAST_JOIN_GROUP:
719 	case MCAST_LEAVE_GROUP:
720 	{
721 		struct group_req greq;
722 		struct sockaddr_in *psin;
723 		struct ip_mreqn mreq;
724 
725 		if (optlen < sizeof(struct group_req))
726 			goto e_inval;
727 		err = -EFAULT;
728 		if (copy_from_user(&greq, optval, sizeof(greq)))
729 			break;
730 		psin = (struct sockaddr_in *)&greq.gr_group;
731 		if (psin->sin_family != AF_INET)
732 			goto e_inval;
733 		memset(&mreq, 0, sizeof(mreq));
734 		mreq.imr_multiaddr = psin->sin_addr;
735 		mreq.imr_ifindex = greq.gr_interface;
736 
737 		if (optname == MCAST_JOIN_GROUP)
738 			err = ip_mc_join_group(sk, &mreq);
739 		else
740 			err = ip_mc_leave_group(sk, &mreq);
741 		break;
742 	}
743 	case MCAST_JOIN_SOURCE_GROUP:
744 	case MCAST_LEAVE_SOURCE_GROUP:
745 	case MCAST_BLOCK_SOURCE:
746 	case MCAST_UNBLOCK_SOURCE:
747 	{
748 		struct group_source_req greqs;
749 		struct ip_mreq_source mreqs;
750 		struct sockaddr_in *psin;
751 		int omode, add;
752 
753 		if (optlen != sizeof(struct group_source_req))
754 			goto e_inval;
755 		if (copy_from_user(&greqs, optval, sizeof(greqs))) {
756 			err = -EFAULT;
757 			break;
758 		}
759 		if (greqs.gsr_group.ss_family != AF_INET ||
760 		    greqs.gsr_source.ss_family != AF_INET) {
761 			err = -EADDRNOTAVAIL;
762 			break;
763 		}
764 		psin = (struct sockaddr_in *)&greqs.gsr_group;
765 		mreqs.imr_multiaddr = psin->sin_addr.s_addr;
766 		psin = (struct sockaddr_in *)&greqs.gsr_source;
767 		mreqs.imr_sourceaddr = psin->sin_addr.s_addr;
768 		mreqs.imr_interface = 0; /* use index for mc_source */
769 
770 		if (optname == MCAST_BLOCK_SOURCE) {
771 			omode = MCAST_EXCLUDE;
772 			add = 1;
773 		} else if (optname == MCAST_UNBLOCK_SOURCE) {
774 			omode = MCAST_EXCLUDE;
775 			add = 0;
776 		} else if (optname == MCAST_JOIN_SOURCE_GROUP) {
777 			struct ip_mreqn mreq;
778 
779 			psin = (struct sockaddr_in *)&greqs.gsr_group;
780 			mreq.imr_multiaddr = psin->sin_addr;
781 			mreq.imr_address.s_addr = 0;
782 			mreq.imr_ifindex = greqs.gsr_interface;
783 			err = ip_mc_join_group(sk, &mreq);
784 			if (err && err != -EADDRINUSE)
785 				break;
786 			greqs.gsr_interface = mreq.imr_ifindex;
787 			omode = MCAST_INCLUDE;
788 			add = 1;
789 		} else /* MCAST_LEAVE_SOURCE_GROUP */ {
790 			omode = MCAST_INCLUDE;
791 			add = 0;
792 		}
793 		err = ip_mc_source(add, omode, sk, &mreqs,
794 				   greqs.gsr_interface);
795 		break;
796 	}
797 	case MCAST_MSFILTER:
798 	{
799 		extern int sysctl_igmp_max_msf;
800 		struct sockaddr_in *psin;
801 		struct ip_msfilter *msf = NULL;
802 		struct group_filter *gsf = NULL;
803 		int msize, i, ifindex;
804 
805 		if (optlen < GROUP_FILTER_SIZE(0))
806 			goto e_inval;
807 		if (optlen > sysctl_optmem_max) {
808 			err = -ENOBUFS;
809 			break;
810 		}
811 		gsf = kmalloc(optlen,GFP_KERNEL);
812 		if (!gsf) {
813 			err = -ENOBUFS;
814 			break;
815 		}
816 		err = -EFAULT;
817 		if (copy_from_user(gsf, optval, optlen)) {
818 			goto mc_msf_out;
819 		}
820 		/* numsrc >= (4G-140)/128 overflow in 32 bits */
821 		if (gsf->gf_numsrc >= 0x1ffffff ||
822 		    gsf->gf_numsrc > sysctl_igmp_max_msf) {
823 			err = -ENOBUFS;
824 			goto mc_msf_out;
825 		}
826 		if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen) {
827 			err = -EINVAL;
828 			goto mc_msf_out;
829 		}
830 		msize = IP_MSFILTER_SIZE(gsf->gf_numsrc);
831 		msf = kmalloc(msize,GFP_KERNEL);
832 		if (!msf) {
833 			err = -ENOBUFS;
834 			goto mc_msf_out;
835 		}
836 		ifindex = gsf->gf_interface;
837 		psin = (struct sockaddr_in *)&gsf->gf_group;
838 		if (psin->sin_family != AF_INET) {
839 			err = -EADDRNOTAVAIL;
840 			goto mc_msf_out;
841 		}
842 		msf->imsf_multiaddr = psin->sin_addr.s_addr;
843 		msf->imsf_interface = 0;
844 		msf->imsf_fmode = gsf->gf_fmode;
845 		msf->imsf_numsrc = gsf->gf_numsrc;
846 		err = -EADDRNOTAVAIL;
847 		for (i=0; i<gsf->gf_numsrc; ++i) {
848 			psin = (struct sockaddr_in *)&gsf->gf_slist[i];
849 
850 			if (psin->sin_family != AF_INET)
851 				goto mc_msf_out;
852 			msf->imsf_slist[i] = psin->sin_addr.s_addr;
853 		}
854 		kfree(gsf);
855 		gsf = NULL;
856 
857 		err = ip_mc_msfilter(sk, msf, ifindex);
858 	mc_msf_out:
859 		kfree(msf);
860 		kfree(gsf);
861 		break;
862 	}
863 	case IP_ROUTER_ALERT:
864 		err = ip_ra_control(sk, val ? 1 : 0, NULL);
865 		break;
866 
867 	case IP_FREEBIND:
868 		if (optlen<1)
869 			goto e_inval;
870 		inet->freebind = !!val;
871 		break;
872 
873 	case IP_IPSEC_POLICY:
874 	case IP_XFRM_POLICY:
875 		err = -EPERM;
876 		if (!capable(CAP_NET_ADMIN))
877 			break;
878 		err = xfrm_user_policy(sk, optname, optval, optlen);
879 		break;
880 
881 	default:
882 		err = -ENOPROTOOPT;
883 		break;
884 	}
885 	release_sock(sk);
886 	return err;
887 
888 e_inval:
889 	release_sock(sk);
890 	return -EINVAL;
891 }
892 
893 int ip_setsockopt(struct sock *sk, int level,
894 		int optname, char __user *optval, int optlen)
895 {
896 	int err;
897 
898 	if (level != SOL_IP)
899 		return -ENOPROTOOPT;
900 
901 	err = do_ip_setsockopt(sk, level, optname, optval, optlen);
902 #ifdef CONFIG_NETFILTER
903 	/* we need to exclude all possible ENOPROTOOPTs except default case */
904 	if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
905 			optname != IP_IPSEC_POLICY &&
906 			optname != IP_XFRM_POLICY &&
907 			!ip_mroute_opt(optname)) {
908 		lock_sock(sk);
909 		err = nf_setsockopt(sk, PF_INET, optname, optval, optlen);
910 		release_sock(sk);
911 	}
912 #endif
913 	return err;
914 }
915 
916 #ifdef CONFIG_COMPAT
917 int compat_ip_setsockopt(struct sock *sk, int level, int optname,
918 			 char __user *optval, int optlen)
919 {
920 	int err;
921 
922 	if (level != SOL_IP)
923 		return -ENOPROTOOPT;
924 
925 	if (optname >= MCAST_JOIN_GROUP && optname <= MCAST_MSFILTER)
926 		return compat_mc_setsockopt(sk, level, optname, optval, optlen,
927 			ip_setsockopt);
928 
929 	err = do_ip_setsockopt(sk, level, optname, optval, optlen);
930 #ifdef CONFIG_NETFILTER
931 	/* we need to exclude all possible ENOPROTOOPTs except default case */
932 	if (err == -ENOPROTOOPT && optname != IP_HDRINCL &&
933 			optname != IP_IPSEC_POLICY &&
934 			optname != IP_XFRM_POLICY &&
935 			!ip_mroute_opt(optname)) {
936 		lock_sock(sk);
937 		err = compat_nf_setsockopt(sk, PF_INET, optname,
938 					   optval, optlen);
939 		release_sock(sk);
940 	}
941 #endif
942 	return err;
943 }
944 
945 EXPORT_SYMBOL(compat_ip_setsockopt);
946 #endif
947 
948 /*
949  *	Get the options. Note for future reference. The GET of IP options gets the
950  *	_received_ ones. The set sets the _sent_ ones.
951  */
952 
953 static int do_ip_getsockopt(struct sock *sk, int level, int optname,
954 			    char __user *optval, int __user *optlen)
955 {
956 	struct inet_sock *inet = inet_sk(sk);
957 	int val;
958 	int len;
959 
960 	if (level != SOL_IP)
961 		return -EOPNOTSUPP;
962 
963 	if (ip_mroute_opt(optname))
964 		return ip_mroute_getsockopt(sk,optname,optval,optlen);
965 
966 	if (get_user(len,optlen))
967 		return -EFAULT;
968 	if (len < 0)
969 		return -EINVAL;
970 
971 	lock_sock(sk);
972 
973 	switch (optname) {
974 	case IP_OPTIONS:
975 	{
976 		unsigned char optbuf[sizeof(struct ip_options)+40];
977 		struct ip_options * opt = (struct ip_options*)optbuf;
978 		opt->optlen = 0;
979 		if (inet->opt)
980 			memcpy(optbuf, inet->opt,
981 			       sizeof(struct ip_options)+
982 			       inet->opt->optlen);
983 		release_sock(sk);
984 
985 		if (opt->optlen == 0)
986 			return put_user(0, optlen);
987 
988 		ip_options_undo(opt);
989 
990 		len = min_t(unsigned int, len, opt->optlen);
991 		if (put_user(len, optlen))
992 			return -EFAULT;
993 		if (copy_to_user(optval, opt->__data, len))
994 			return -EFAULT;
995 		return 0;
996 	}
997 	case IP_PKTINFO:
998 		val = (inet->cmsg_flags & IP_CMSG_PKTINFO) != 0;
999 		break;
1000 	case IP_RECVTTL:
1001 		val = (inet->cmsg_flags & IP_CMSG_TTL) != 0;
1002 		break;
1003 	case IP_RECVTOS:
1004 		val = (inet->cmsg_flags & IP_CMSG_TOS) != 0;
1005 		break;
1006 	case IP_RECVOPTS:
1007 		val = (inet->cmsg_flags & IP_CMSG_RECVOPTS) != 0;
1008 		break;
1009 	case IP_RETOPTS:
1010 		val = (inet->cmsg_flags & IP_CMSG_RETOPTS) != 0;
1011 		break;
1012 	case IP_PASSSEC:
1013 		val = (inet->cmsg_flags & IP_CMSG_PASSSEC) != 0;
1014 		break;
1015 	case IP_TOS:
1016 		val = inet->tos;
1017 		break;
1018 	case IP_TTL:
1019 		val = (inet->uc_ttl == -1 ?
1020 		       sysctl_ip_default_ttl :
1021 		       inet->uc_ttl);
1022 		break;
1023 	case IP_HDRINCL:
1024 		val = inet->hdrincl;
1025 		break;
1026 	case IP_MTU_DISCOVER:
1027 		val = inet->pmtudisc;
1028 		break;
1029 	case IP_MTU:
1030 	{
1031 		struct dst_entry *dst;
1032 		val = 0;
1033 		dst = sk_dst_get(sk);
1034 		if (dst) {
1035 			val = dst_mtu(dst);
1036 			dst_release(dst);
1037 		}
1038 		if (!val) {
1039 			release_sock(sk);
1040 			return -ENOTCONN;
1041 		}
1042 		break;
1043 	}
1044 	case IP_RECVERR:
1045 		val = inet->recverr;
1046 		break;
1047 	case IP_MULTICAST_TTL:
1048 		val = inet->mc_ttl;
1049 		break;
1050 	case IP_MULTICAST_LOOP:
1051 		val = inet->mc_loop;
1052 		break;
1053 	case IP_MULTICAST_IF:
1054 	{
1055 		struct in_addr addr;
1056 		len = min_t(unsigned int, len, sizeof(struct in_addr));
1057 		addr.s_addr = inet->mc_addr;
1058 		release_sock(sk);
1059 
1060 		if (put_user(len, optlen))
1061 			return -EFAULT;
1062 		if (copy_to_user(optval, &addr, len))
1063 			return -EFAULT;
1064 		return 0;
1065 	}
1066 	case IP_MSFILTER:
1067 	{
1068 		struct ip_msfilter msf;
1069 		int err;
1070 
1071 		if (len < IP_MSFILTER_SIZE(0)) {
1072 			release_sock(sk);
1073 			return -EINVAL;
1074 		}
1075 		if (copy_from_user(&msf, optval, IP_MSFILTER_SIZE(0))) {
1076 			release_sock(sk);
1077 			return -EFAULT;
1078 		}
1079 		err = ip_mc_msfget(sk, &msf,
1080 				   (struct ip_msfilter __user *)optval, optlen);
1081 		release_sock(sk);
1082 		return err;
1083 	}
1084 	case MCAST_MSFILTER:
1085 	{
1086 		struct group_filter gsf;
1087 		int err;
1088 
1089 		if (len < GROUP_FILTER_SIZE(0)) {
1090 			release_sock(sk);
1091 			return -EINVAL;
1092 		}
1093 		if (copy_from_user(&gsf, optval, GROUP_FILTER_SIZE(0))) {
1094 			release_sock(sk);
1095 			return -EFAULT;
1096 		}
1097 		err = ip_mc_gsfget(sk, &gsf,
1098 				   (struct group_filter __user *)optval, optlen);
1099 		release_sock(sk);
1100 		return err;
1101 	}
1102 	case IP_PKTOPTIONS:
1103 	{
1104 		struct msghdr msg;
1105 
1106 		release_sock(sk);
1107 
1108 		if (sk->sk_type != SOCK_STREAM)
1109 			return -ENOPROTOOPT;
1110 
1111 		msg.msg_control = optval;
1112 		msg.msg_controllen = len;
1113 		msg.msg_flags = 0;
1114 
1115 		if (inet->cmsg_flags & IP_CMSG_PKTINFO) {
1116 			struct in_pktinfo info;
1117 
1118 			info.ipi_addr.s_addr = inet->rcv_saddr;
1119 			info.ipi_spec_dst.s_addr = inet->rcv_saddr;
1120 			info.ipi_ifindex = inet->mc_index;
1121 			put_cmsg(&msg, SOL_IP, IP_PKTINFO, sizeof(info), &info);
1122 		}
1123 		if (inet->cmsg_flags & IP_CMSG_TTL) {
1124 			int hlim = inet->mc_ttl;
1125 			put_cmsg(&msg, SOL_IP, IP_TTL, sizeof(hlim), &hlim);
1126 		}
1127 		len -= msg.msg_controllen;
1128 		return put_user(len, optlen);
1129 	}
1130 	case IP_FREEBIND:
1131 		val = inet->freebind;
1132 		break;
1133 	default:
1134 		release_sock(sk);
1135 		return -ENOPROTOOPT;
1136 	}
1137 	release_sock(sk);
1138 
1139 	if (len < sizeof(int) && len > 0 && val>=0 && val<=255) {
1140 		unsigned char ucval = (unsigned char)val;
1141 		len = 1;
1142 		if (put_user(len, optlen))
1143 			return -EFAULT;
1144 		if (copy_to_user(optval,&ucval,1))
1145 			return -EFAULT;
1146 	} else {
1147 		len = min_t(unsigned int, sizeof(int), len);
1148 		if (put_user(len, optlen))
1149 			return -EFAULT;
1150 		if (copy_to_user(optval,&val,len))
1151 			return -EFAULT;
1152 	}
1153 	return 0;
1154 }
1155 
1156 int ip_getsockopt(struct sock *sk, int level,
1157 		  int optname, char __user *optval, int __user *optlen)
1158 {
1159 	int err;
1160 
1161 	err = do_ip_getsockopt(sk, level, optname, optval, optlen);
1162 #ifdef CONFIG_NETFILTER
1163 	/* we need to exclude all possible ENOPROTOOPTs except default case */
1164 	if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1165 			!ip_mroute_opt(optname)) {
1166 		int len;
1167 
1168 		if (get_user(len,optlen))
1169 			return -EFAULT;
1170 
1171 		lock_sock(sk);
1172 		err = nf_getsockopt(sk, PF_INET, optname, optval,
1173 				&len);
1174 		release_sock(sk);
1175 		if (err >= 0)
1176 			err = put_user(len, optlen);
1177 		return err;
1178 	}
1179 #endif
1180 	return err;
1181 }
1182 
1183 #ifdef CONFIG_COMPAT
1184 int compat_ip_getsockopt(struct sock *sk, int level, int optname,
1185 			 char __user *optval, int __user *optlen)
1186 {
1187 	int err;
1188 
1189 	if (optname == MCAST_MSFILTER)
1190 		return compat_mc_getsockopt(sk, level, optname, optval, optlen,
1191 			ip_getsockopt);
1192 
1193 	err = do_ip_getsockopt(sk, level, optname, optval, optlen);
1194 
1195 #ifdef CONFIG_NETFILTER
1196 	/* we need to exclude all possible ENOPROTOOPTs except default case */
1197 	if (err == -ENOPROTOOPT && optname != IP_PKTOPTIONS &&
1198 			!ip_mroute_opt(optname)) {
1199 		int len;
1200 
1201 		if (get_user(len, optlen))
1202 			return -EFAULT;
1203 
1204 		lock_sock(sk);
1205 		err = compat_nf_getsockopt(sk, PF_INET, optname, optval, &len);
1206 		release_sock(sk);
1207 		if (err >= 0)
1208 			err = put_user(len, optlen);
1209 		return err;
1210 	}
1211 #endif
1212 	return err;
1213 }
1214 
1215 EXPORT_SYMBOL(compat_ip_getsockopt);
1216 #endif
1217 
1218 EXPORT_SYMBOL(ip_cmsg_recv);
1219 
1220 EXPORT_SYMBOL(ip_getsockopt);
1221 EXPORT_SYMBOL(ip_setsockopt);
1222